[PATCH libinput] tablet: ignore tools already in proximity at startup

[Peter Hutterer]

Require a tool to be moved into proximity before we handle any events from it.
This requires the user to lift the tool for first use but a tool that's
already on the tablet on init is likely to send garbage anyway and interfere.
This way users can leave the mouse/pen on the tablet overnight and their
events won't interfere until they actually use it.

Reported-by: Jason Gerecke <killertofu at gmail.com>
Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>
---
 src/evdev-tablet.c | 10 +++++++++-
 test/tablet.c      | 43 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 52 insertions(+), 1 deletion(-)

diff --git a/src/evdev-tablet.c b/src/evdev-tablet.c
index 4524202..1b87ec3 100644
--- a/src/evdev-tablet.c
+++ b/src/evdev-tablet.c
@@ -190,7 +190,7 @@ tablet_update_tool(struct tablet_dispatch *tablet,
 		tablet_set_status(tablet, TABLET_TOOL_ENTERING_PROXIMITY);
 		tablet_unset_status(tablet, TABLET_TOOL_OUT_OF_PROXIMITY);
 	}
-	else
+	else if (!tablet_has_status(tablet, TABLET_TOOL_OUT_OF_PROXIMITY))
 		tablet_set_status(tablet, TABLET_TOOL_LEAVING_PROXIMITY);
 }
 
@@ -863,6 +863,9 @@ tablet_flush(struct tablet_dispatch *tablet,
 				tablet->current_tool_id,
 				tablet->current_tool_serial);
 
+	if (tablet_has_status(tablet, TABLET_TOOL_OUT_OF_PROXIMITY))
+		return;
+
 	if (tablet_has_status(tablet, TABLET_TOOL_LEAVING_PROXIMITY)) {
 		/* Release all stylus buttons */
 		memset(tablet->button_state.stylus_buttons,
@@ -910,7 +913,11 @@ tablet_flush(struct tablet_dispatch *tablet,
 
 		tablet_change_to_left_handed(device);
 	}
+}
 
+static inline void
+tablet_reset_state(struct tablet_dispatch *tablet)
+{
 	/* Update state */
 	memcpy(&tablet->prev_button_state,
 	       &tablet->button_state,
@@ -941,6 +948,7 @@ tablet_process(struct evdev_dispatch *dispatch,
 		break;
 	case EV_SYN:
 		tablet_flush(tablet, device, time);
+		tablet_reset_state(tablet);
 		break;
 	default:
 		log_error(device->base.seat->libinput,
diff --git a/test/tablet.c b/test/tablet.c
index d7486cb..94aa93d 100644
--- a/test/tablet.c
+++ b/test/tablet.c
@@ -1157,6 +1157,48 @@ START_TEST(tool_capabilities)
 }
 END_TEST
 
+START_TEST(tool_in_prox_before_start)
+{
+	struct libinput *li;
+	struct litest_device *dev = litest_current_device();
+	struct libinput_event *event;
+	struct axis_replacement axes[] = {
+		{ ABS_DISTANCE, 10 },
+		{ ABS_TILT_X, 0 },
+		{ ABS_TILT_Y, 0 },
+		{ -1, -1 }
+	};
+	const char *devnode;
+
+	litest_tablet_proximity_in(dev, 10, 10, axes);
+
+	/* for simplicity, we create a new litest context */
+	devnode = libevdev_uinput_get_devnode(dev->uinput);
+	li = litest_create_context();
+	libinput_path_add_device(li, devnode);
+
+	litest_wait_for_event_of_type(li,
+				      LIBINPUT_EVENT_DEVICE_ADDED,
+				      -1);
+	event = libinput_get_event(li);
+	libinput_event_destroy(event);
+
+	litest_assert_empty_queue(li);
+	litest_tablet_motion(dev, 10, 20, axes);
+	litest_tablet_motion(dev, 30, 40, axes);
+	litest_assert_empty_queue(li);
+	litest_event(dev, EV_KEY, BTN_STYLUS, 1);
+	litest_event(dev, EV_SYN, SYN_REPORT, 0);
+	litest_event(dev, EV_KEY, BTN_STYLUS, 1);
+	litest_event(dev, EV_SYN, SYN_REPORT, 0);
+	litest_assert_empty_queue(li);
+	litest_tablet_proximity_out(dev);
+	litest_assert_empty_queue(li);
+
+	libinput_unref(li);
+}
+END_TEST
+
 START_TEST(mouse_tool)
 {
 	struct litest_device *dev = litest_current_device();
@@ -1615,6 +1657,7 @@ main(int argc, char **argv)
 {
 	litest_add("tablet:tool", tool_ref, LITEST_TABLET | LITEST_TOOL_SERIAL, LITEST_ANY);
 	litest_add_no_device("tablet:tool", tool_capabilities);
+	litest_add("tablet:tool", tool_in_prox_before_start, LITEST_TABLET, LITEST_ANY);
 	litest_add("tablet:tool_serial", tool_serial, LITEST_TABLET | LITEST_TOOL_SERIAL, LITEST_ANY);
 	litest_add("tablet:tool_serial", serial_changes_tool, LITEST_TABLET | LITEST_TOOL_SERIAL, LITEST_ANY);
 	litest_add("tablet:tool_serial", invalid_serials, LITEST_TABLET | LITEST_TOOL_SERIAL, LITEST_ANY);
-- 
2.1.0